<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .div-main {
            width: 500px;
            height: 400px;
            background: #75003b;
        }

        .item1 {
            float: left;
            width: 100px;
            height: 100px;
            text-align: center;
            display:  block;
            background: #00752d;
        }
        .item2 {
            float: left;
            /*width: 100px;*/
            /*height: 100px;*/
            background: #00752d;
        }
    </style>

<body>
<div class="div-main">
    <span class="item1" style="background: #7ea9ff;">12</span>
    <span class="item2" style="background: #ff5583;">13</span>
</div>
</body>


</html>